High pressure boiler



March 3, 1936. H. J. KERR 2,032,368

HIGH PRESSURE BOILER Original Filed April 22, 1930 5 Sheets-Sheet lINVENTOR ATTORNEYS.

March 3,1936. KERR 2,032,368

HIGH PRESSURE BOILER Original Filed April 22, 1930 3 Sheets Sheet 2 Fi:Z

INVENTQR' BY 2. Z l/M W ATTORNEY March 3, 1936. H. J. KERR 2,032,363

HIGH PRESSURE BOILER Original Filed April 22, 1930 3 Sheets-Sheet 3 Fig-,8

- I ,A.%r W WATTORNEYS.

Patented Mar. 3, 1936 PATENT OFFICE HIGH PRESSURE BOILER Howard J. Kerr,Westfield, N. J., assignor to The Babcock & Wilcox Company, Bayonne, N.J., a corporation of New Jersey Application April 22, 1930, Serial No.446,221 RenewedMarch 15, 1934 7 Claims.

This invention relates to a novel and improved form of boiler,particularly one of the high pressure type, and the novel features willbe best understood from the following description and the annexeddrawings, in which I have shown selected embodiments of the inventionand in which:

Fig. l is a semi-diagrammatic view showing one embodiment which theinvention may take.

Fig. 2 is a view similar to Fig. 1 but illustrating a second embodiment.

Fig. 3 is a third view similar to Fig. 1 but showing still anotherembodiment.

Referring first to Fig. 1, I have shown therein a furnace I adapted toburn fuel by any suitable means here exemplified as a pulverized fuelburner 2. The furnace has a single upwardly extending pass across whichis disposed the boiler.

In this case, the boiler is shown as of the type having an inlet 3 andan outlet I which are joined together by a continuous conduit 5. In theillustration, this conduit is shown as being formed of a plurality oftubes joined together by return bends, so as to form, in effect, asingle element. Of course, other forms may be used, it only beingnecessary that there should bea continuous passage for the flow of waterand/or steam through the passage and, for the sake of simplicity, Ishall hereinafter refer to the boiler as having a continuous conduit,the particular form of the conduit being subject to considerable changein design without affecting the invention. In the drawings, the inletand outlet are shown as headers, and of course it is understood thatthere are a large number of conduits 5 connected to these headers, butall carrying fluid in the same direction from the inlet header to theoutlet header.

Water is supplied from a pipe 6 and forced by a feed pump I through apipe 8 to the inlet, a suitable valve 9 being provided to regulate theflow of water. There is discharged at the outlet 4 of the boiler amixture of steam and water at high pressure, and this mixture isconducted through the pipe I0 to a separator II. Here separation takesplace and the water is collected in the bottom of the separator and thesteam in the top, the water line being indicated at I2. If desired, thiswater line may be maintained by means of a connection I3 from the feedpump, a valve l4 being supplied in this connection and controlled bymeans of a float I5 connected to the valve by a chain I6.

Steam from the separator passes through the pipe II to a pump I8 whichforces it through a superheater here shown as a superheater of theradiant heat type, located at I9 in a wall of the combustion chamber ofthe furnace.

Fromthe superheater the steam is led through the pipe M to an engine orother point of use. 5 A certain proportion of the superheated steam maybe supplied to the turbines driving the pumps I1 and I8 by means of thepipes 22 and 23, respectively, the flow of superheated steam in the pipe22 being controlled by a valve 24 which is 10 also operated from thefloat I5 by means of a chain 25. Flow through the pipe 23 is controlledby a hand valve 26.

A portion of the superheated steam is diverted from the main 2| throughthe pipe 21 into the 15 water space of the separator and is theredischarged as indicated at 28. Of course, due to the additional pressureimpressed upon it by the pump I8, the superheated steam thus dischargedis at a higher pressure than is the steam and water 20 entering theseparator through the pipe I0, and this superheated steam gives up itssuperheat to evaporate some of the water in the separator formingsaturated steam which mingles with that entering through the pipe I0. Inthe pipe 21 is '25 a valve 29, by means of which flow of superheatedsteam to the separator may be regulated.

By proper adjustment of the various parts described above, it ispossible for the amount of steam supplied at 28 to the water in theseparator 30 to be so regulated as to evaporate the excess waterintroduced into the separator from the pipe I 0., This means that anexcess of steam over that required for power or other purposes, leavingthrough the pipe 2| can be superheated in 35 the radiantly heatedsuperheater I9, this excess conveying suificient heat in its superheatto supply the heat necessary to completely evaporate all of the waterseparated out in the separator I I from the wet saturated steam enteringthrough 4t the pipe I 0. By employing the steam booster pump I8, thesteam passing through the superheater I9 is under control and there isno danger of the superheater tubes being burned out. At the same timethis pump increases the pressure 45 of the steam sufiiciently so thatthe superheated steam leaving through the pipe 2I is at a slightlyhigher pressure than the saturated steam and Water in the separator II,and the superheated steam will therefore flow through the pipe 21 50 asregulated by the valve 29 into the separator II and assist inevaporating the excess water carried in through the pipe II! by the wetsaturated'steam from the boiler.

Referring now to Fig. 2, I have shown therein 55 rated steam from theboiler.

an apparatus similar to what is shown in Fig. 1, and in which similarreference characters have been used to a large extent. In this form,however, the entire quantity of superheated steam is passed through thepipe 2| which is connected to a coil 30 in the separator H. The outletof this coil is connected to a pipe 3| which forms the steam main. Inthis manner all of the steam required for power or other purposes issuperheated to a temperature above that required in actual use, theexcess heat being given up in the separator II in passing through thecoil 30 to assist in evaporatingthe excess water carried into theseparator ll through pipe ID by wet satu- The same result is attained aswith the construction described in connection with Fig. 1, but byemploying a modified construction and method of operation.

In this form, the valve 26 controlling the supply of steam to theturbine driving the pump 18 is used as before, but the valve 24'controlling the supply of steam to the turbine driving the feed pump 1is thermostatically controlled by athermostat 32 disposed at the outletend of the superheater. In this manner the rate of feed to the boiler isregulated by means of the temperature of the superheated steam leavingthe superheater and is so arranged that after giving up part of its heatto evaporate the excess water in the separator II, the steam leavesthrough the pipe 3i with the necessary superheat required for power orother purposes.

Referring now to Fig; 3, I have shown a difierent embodiment whichaccomplishes the same result as the two embodiments previouslydescribed, but employs a difierent method of operation and eliminatesthe superheated steam booster pump.

The water is supplied by a feed pump 34 to a pipe 35 which-is connectedto the inlet 3 of the boiler and also to an inlet 36 of a secondary orauxiliary boiler 31 in the same setting as the main boiler 5. Thisboiler 31 is smaller than boiler 5. The pressure of the water enteringboth boilers through headers 36 and 3, respectively, is approximatelythe same, but with this construction of boiler employing continuousconduits, the pressure drop through the larger boiler 5 will, of course,be greater than the pressure drop through the smaller boiler 31, so thatthe resulting steam or steam and water leaving through the outlet 38 ofthe small boiler 31, will be at a higher pressure than that leavingthrough the outlet ID of the larger boiler 5 and consequently the steamleaving the smaller boiler will have a greater heat content per unit.In' addition to the increased pressure the relation between the smallboiler 31 and the larger boiler 5 can be such that all of the waterpassing through the smaller boiler 31 can be evaporated or evensuperheated before leaving. The steam and water is discharged from themain boiler 5 in the usual manner through the outlet l0 and enters theseparator I I, the water separating from the steam and occupying thelower portion of the chamber while the steam occupies the upper portion.The

.higher pressure steam from the smaller boiler,

whether saturated or superheated, enters the separator H through thepipe 38 and 'gives up its excess heat to the water separated out fromthe .wet saturated steam delivered from the main boiler, in this wayevaporating part of it, the steam thus formed mingling with theseparated saturated steam and flowing through the pipe I I and thenthrough the radiantly heated superheater l9 to the outlet 33 to be usedfor power When only sufficient water to meet the steam.

requirements for power or other purposes is fed to such a boiler, all ofthe water must be evaporated in the boiler section before the steam goesto the superheater, and due to differences in load conditions, it ispossible that all of the steam might be evaporated before reaching theend of the so-called boiler section and superheating of the steam mighttake place in this section, in which case the tubes in which superheattakes place might possibly be burned out. With the method of operation Ihave described, this situation cannot arise as in every case wetsaturated steam is discharged from the boiler section into a separator,the water being separated out and evaporated by means of excess heatfrom superheated steam or steam at higher pressure and the total amountof saturated steam thus formed superheated as required. In all cases dryor nearly dry saturated steam is supplied to the superheater.

I claim:

1. In combination with a furnace providing hot products of combustionand a radiant heat zone, a fluid vapor generating circuit absorbing thesensible heat of said products of combustion to convert a major portionof the fluid in said circuit into vapor in a single passagetherethrough, a separator for liquid andvapor, a superheater in theradiant heat zone with a supply from the vapor space of said separatorand a discharge beneath the liquid level thereof to convert the excessliquid in the separator into vapor, and means regulating the supply ofliquid to said vapor generating circuit to maintain only a predeterminedexcess in said separator.

2. The method of operating a vapor generator with a fluid circuit in aconvection heat zone and a vapor superheating circuit in a radiant heatzone, and both of said circuits connected with the same liquid and vaporseparator, which comprises circulating only a slight excess of liquidthrough the fluid circuit to generate a major portion of the vapor fromsensible heat in the gases passing the convection heat zone, permittingseparation of vapor and liquid in the separator, and passing vapor fromthe separator through the vapor superheating circuit and back to theseparator to generate a minor portion of the vapor from the slightexcess of liquid always passing through the fluid circuit.

V 3. The method of operating a vapor generator including a heatedfurnace, a flow path continuous from inlet to outlet with long smallbore conduit portions arranged for parallel flow, a separator for liquidand vapor, and a superheater, whichcomprises supplying a liquidthroughout the flow path at a rate providing an excess preventing scaledeposit while generating vapor, separating the excess liquid to producedry saturated vapor, superheating the dry saturated vapor and usingatleast some of it to evaporate excess liquid.

4. The method of operating a vapor generator including a heated furnace,a flow path continuous from inlet to outlet with long small bore conduitportions arranged for parallel flow, a separator for liquid and vapor,and a superheater, which comprises supplying liquid throughout the fiowpath at a rate providing an excess preventing scale deposit whilegenerating vapor, separating the excess liquid to provide dry .saturatedvapor,- raising the pressure of the dry saturated vapor and superheatingthe same, and then using at least some of the higher pressuresuperheated vapor in fluid contact to evaporate excess liquid.

5. The method of operating a vapor generator with a liquid and vaporcircuit and a vapor superheating circuit, both of said circuitsconnected with the same liquid and vapor separator, which comprisescirculating only a slight excess of liquid through the liquid and vaporcircuit to generate a major portion of the vapor from sensible heat inthe gases passing the liquid and vapor circuit, permitting separation ofthe vapor and liquid in the separator, and passing vapor from theseparator through the vapor superheating circuit and back to theseparator to generate a minor portion of the vapor from the slightexcess of liquid always passing through the fluid circuit.

6. The method of operating a vapor generator including a heatingfurnace, a fiow path continuous from inlet to outlet with long smallbore conduit .portions arranged for parallel flow, a separator forliquid and vapor, and a superheater, which comprises supplying a liquidthroughout the flow path at a rate providing an excess preventing scaledeposit while generating vapor, separating the excess liquid to providedry saturated vapor,- superheating the dry saturated vapor and using atleast some of it to evaporate excess liquid in the separator whilemaintaining a constant level of liquid in the separator.

a vapor generator including 7. In combination, a heated furnace, a flowpath continuous from inlet to outlet with long small bore conduitportions arranged for parallel flow, a separator for liquid and vapor; aseparator receiving the discharge irom said fiow path, a secondary vaporgenerator also heated by the aforesaid furnace and including a fiow pathcontinuous from inlet to outlet with long small bore conduit portionsarranged for parallel fiow, means for supplying liquid to the fiow pathof the first mentioned vapor generator at a rate providing an excesspreventing scale deposit while generating'vapor, means for supplyingliquid to the last'mentloned vapor generator, the generators having adifieren'tial in pressure drop between the two whereby the last namedgenerator operates at a higher pressure than the first named generator,and means connecting the last named generator to the separator of thefirst named generator to introduce vapor of higher pressure andtemperature into the separator to evaporate excess liquid discharge bythe first named generator.

, HOWARD J. KERR CERTIFICATE OF CORRECTION,

Patent, No. 032,368. Marc n3, 1936.

HOWARD J.

' It is hereby certified that error appears in the printedspec'ificationfoi the above numbered patent requiring correction asfollows: Page 3, first" coLumn, line 29, claim 6, for the word "heating"read heated; and second column, line 13, claim 7, for "a" I Henry VanAredale Acting Commissioner of Patent-=1.

read said; and that the saidLetters Pat-

